1. Field of the Invention:
This invention relates generally to a television signal generator. More particularly, the invention relates to a television signal generator in which a television test pattern signal or other television signal is generated using digital circuits. The signal may be used for resolution measurements of a television picture tube.
2. Description of the Prior Art:
A known television signal generator which produces a television signal using digital circuits has the disadvantage that an undesirable, stepped portion appears along the outline of the pattern or shape in the television picture reproduced from the signal, due to the digital waveform of the signal.
Moreover, since the signal consists of bipolar pulses which jump abruptly from one level to another, the picture cannot include portions representing an intermediate luminance level.
Another known television signal generator is used, which produces a television signal with an image pick-up tube or a monoscope tube. The waveform of the signal can be changed by adjusting the focus of the image pick-up tube or the monoscope tube. However, it is very difficult to control or adjust the degree of such focus adjustment to an exact value, so the pattern or shape reproduced from such a television signal on a picture tube cannot be accurately predetermined. Therefore, reliable measured values cannot be obtained.